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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
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package javax.swing.plaf.metal;

import sun.swing.SwingUtilities2;
import sun.awt.AppContext;

import javax.swing.*;
import javax.swing.border.*;
import javax.swing.plaf.basic.*;
import java.awt.*;
import java.awt.event.*;
import java.beans.*;
import javax.swing.plaf.*;


MetalButtonUI implementation


Warning:
Serialized objects of this class will not be compatible with
future Swing releases. The current serialization support is
appropriate for short term storage or RMI between applications running
the same version of Swing.  As of 1.4, support for long term storage
of all JavaBeans
has been added to the java.beans package. Please see XMLEncoder. 
Author:Tom Santos
/**
 * MetalButtonUI implementation
 * <p>
 * <strong>Warning:</strong>
 * Serialized objects of this class will not be compatible with
 * future Swing releases. The current serialization support is
 * appropriate for short term storage or RMI between applications running
 * the same version of Swing.  As of 1.4, support for long term storage
 * of all JavaBeans
 * has been added to the <code>java.beans</code> package.
 * Please see {@link java.beans.XMLEncoder}.
 *
 * @author Tom Santos
 */
@SuppressWarnings("serial") // Same-version serialization only
public class MetalButtonUI extends BasicButtonUI {

    // NOTE: These are not really needed, but at this point we can't pull
    // them. Their values are updated purely for historical reasons.
    
The color of the focused button.

/**
     * The color of the focused button.
     */
    protected Color focusColor;

    
The color of the selected button.

/**
     * The color of the selected button.
     */
    protected Color selectColor;

    
The color of the disabled color.

/**
     * The color of the disabled color.
     */
    protected Color disabledTextColor;

    private static final Object METAL_BUTTON_UI_KEY = new Object();

    // ********************************
    //          Create PLAF
    // ********************************

    
Constructs a MetalButtonUI. 
/**
     * Constructs a {@code MetalButtonUI}.
     */
    public MetalButtonUI() {}

    
Returns an instance of MetalButtonUI. 
Params:
  • c – a component
Returns:an instance of MetalButtonUI
/**
     * Returns an instance of {@code MetalButtonUI}.
     *
     * @param c a component
     * @return an instance of {@code MetalButtonUI}
     */
    public static ComponentUI createUI(JComponent c) {
        AppContext appContext = AppContext.getAppContext();
        MetalButtonUI metalButtonUI =
                (MetalButtonUI) appContext.get(METAL_BUTTON_UI_KEY);
        if (metalButtonUI == null) {
            metalButtonUI = new MetalButtonUI();
            appContext.put(METAL_BUTTON_UI_KEY, metalButtonUI);
        }
        return metalButtonUI;
    }

    // ********************************
    //          Install
    // ********************************
    public void installDefaults(AbstractButton b) {
        super.installDefaults(b);
    }

    public void uninstallDefaults(AbstractButton b) {
        super.uninstallDefaults(b);
    }

    // ********************************
    //         Create Listeners
    // ********************************
    protected BasicButtonListener createButtonListener(AbstractButton b) {
        return super.createButtonListener(b);
    }


    // ********************************
    //         Default Accessors
    // ********************************

    
Returns the color of the selected button.

Returns:the color of the selected button
/**
     * Returns the color of the selected button.
     *
     * @return the color of the selected button
     */
    protected Color getSelectColor() {
        selectColor = UIManager.getColor(getPropertyPrefix() + "select");
        return selectColor;
    }

    
Returns the color of a disabled text.

Returns:the color of a disabled text
/**
     * Returns the color of a disabled text.
     *
     * @return the color of a disabled text
     */
    protected Color getDisabledTextColor() {
        disabledTextColor = UIManager.getColor(getPropertyPrefix() +
                                               "disabledText");
        return disabledTextColor;
    }

    
Returns the color of the focused button.

Returns:the color of the focused button
/**
     * Returns the color of the focused button.
     *
     * @return the color of the focused button
     */
    protected Color getFocusColor() {
        focusColor = UIManager.getColor(getPropertyPrefix() + "focus");
        return focusColor;
    }

    // ********************************
    //          Paint
    // ********************************
    
If necessary paints the background of the component, then
invokes paint.

Params:
  • g – Graphics to paint to
  • c – JComponent painting on
Throws:
See Also:
Since:1.5
/**
     * If necessary paints the background of the component, then
     * invokes <code>paint</code>.
     *
     * @param g Graphics to paint to
     * @param c JComponent painting on
     * @throws NullPointerException if <code>g</code> or <code>c</code> is
     *         null
     * @see javax.swing.plaf.ComponentUI#update
     * @see javax.swing.plaf.ComponentUI#paint
     * @since 1.5
     */
    public void update(Graphics g, JComponent c) {
        AbstractButton button = (AbstractButton)c;
        if ((c.getBackground() instanceof UIResource) &&
                  button.isContentAreaFilled() && c.isEnabled()) {
            ButtonModel model = button.getModel();
            if (!MetalUtils.isToolBarButton(c)) {
                if (!model.isArmed() && !model.isPressed() &&
                        MetalUtils.drawGradient(
                        c, g, "Button.gradient", 0, 0, c.getWidth(),
                        c.getHeight(), true)) {
                    paint(g, c);
                    return;
                }
            }
            else if (model.isRollover() && MetalUtils.drawGradient(
                        c, g, "Button.gradient", 0, 0, c.getWidth(),
                        c.getHeight(), true)) {
                paint(g, c);
                return;
            }
        }
        super.update(g, c);
    }

    protected void paintButtonPressed(Graphics g, AbstractButton b) {
        if ( b.isContentAreaFilled() ) {
            Dimension size = b.getSize();
            g.setColor(getSelectColor());
            g.fillRect(0, 0, size.width, size.height);
        }
    }

    protected void paintFocus(Graphics g, AbstractButton b,
                              Rectangle viewRect, Rectangle textRect, Rectangle iconRect){

        Rectangle focusRect = new Rectangle();
        String text = b.getText();
        boolean isIcon = b.getIcon() != null;

        // If there is text
        if ( text != null && !text.isEmpty()) {
            if ( !isIcon ) {
                focusRect.setBounds( textRect );
            }
            else {
                focusRect.setBounds( iconRect.union( textRect ) );
            }
        }
        // If there is an icon and no text
        else if ( isIcon ) {
            focusRect.setBounds( iconRect );
        }

        g.setColor(getFocusColor());
        g.drawRect((focusRect.x-1), (focusRect.y-1),
                  focusRect.width+1, focusRect.height+1);

    }


    protected void paintText(Graphics g, JComponent c, Rectangle textRect, String text) {
        AbstractButton b = (AbstractButton) c;
        ButtonModel model = b.getModel();
        FontMetrics fm = SwingUtilities2.getFontMetrics(c, g);
        int mnemIndex = b.getDisplayedMnemonicIndex();

        /* Draw the Text */
        if(model.isEnabled()) {
            /*** paint the text normally */
            g.setColor(b.getForeground());
        }
        else {
            /*** paint the text disabled ***/
            g.setColor(getDisabledTextColor());
        }
        SwingUtilities2.drawStringUnderlineCharAt(c, g,text,mnemIndex,
                                  textRect.x, textRect.y + fm.getAscent());
    }
}